1. Consider the BALANCED gas-phase reaction: Note that the full Lewis dot structures are NOT given, only the bond multiplicities. H C=O + 2 H-H CEO H-H H-C-O-H 1,079 436 C-H 414 C-O 351 0-H 460 Estimate AH° (in kJ) for this reaction using the following bond enthalpy data (all bond enthalpies in the above table are in kJ/mol). H

Q. Use the average bond energy approach to calculate the enthalpy for the complete combustion of CH3OH(g).

Using bond enthalpies in the table, estimate AH for the following gas-phase reactions. Average Bond Enthalpies (kJ/mol) Single Bonds C-H C-C C-N C-O C-F C-Cl C-Br C-I C-S 413 |N-H 348 |N-N 293 N-O 358 |N-F 485 |N-Cl 328 N-Br 243 276 240 259 CH–C1 242 193 Br-Br Multiple Bonds C=C C=C C=N C=N 614 839 615 391 O-H 0-0 163 201 O-F 272 O-Cl 200 O-I 201 463 146 190 203 234 339 H-H S-H 436 S-F 567 S-Cl 327 253 H-F H-Cl 431 S-Br 218 H-Br 366 S-S 266 H-I 299 |N=N 418 0=0 |N=N 941 |N=O 607 495 Part C Estimate AH for the reaction. Express your answer using one significant figure. AH = Submit —| ΑΣΦ Provide Feedback H H-N-N-H+CI-CI-2 H-N-CI -H+C₁_a_ Previous Answers Request Answer HH X Incorrect; Try Again; 3 attempts remaining ? kJ

Use bond enthalpies (Table 9.5 page 303) to estimate AH (kJ/mol) for the following gas-phase reaction. H H H. H+ C=C H,O H-C-C-H + | | OH H H. H Ethylene Water Ethanol

(Q77) The standard Gibbs free energy (AG°rxn) for the formation of sulfur trioxide from sulfur dioxide and oxygen gas is -72.3 kJ/mol. The balanced chemical equation is SO2 (g) + ½ O2 (g) - - SO3 (g). What will be the Gibbs Free energy of the reaction (in kJ/mol) if it takes place at a low temperature of -25.3 °C and the concentrations of three gases are: SO2 = 0.183 M O2 = 0.146 M SO3 = 1.05 M

Use Table 9.4 to calculate an approximate enthalpy or heat of reaction for the combustion of one mole of methane gas (CH4) to form gaseous H₂O and CO₂. What Volume (in L) of methane is needed to produce 2715 kJ of heat for methane gas at 33 °C and 9.50 atm pressure? Hint given in feedback

Using the table of bond enthalpies in your textbook, predict ArH for the following reaction. Express your answer in kJ/mol. HCECH + 2 H2 → H3C-CH3

Given that the average bond energies for C-H and C-Br bonds are 413 and 276 kJ/mol, respectively. Calculate the heat of atomization of bromoform (CHBr3) (kJ/mol) and show the calculation step.

Using bond energies from the table, estimate ΔH for the reaction below. The OH group on the product side is attached to a carbon.CH2=CH2(g) + H2O(g) ↔ CH3CH2OH(g) Bond Energies, kJ/mol Single Bonds   H C N O S F Cl Br I H 432                 C 411 346               N 386 305 167             O 459 358 201 142           S 363 272 --- --- 286         F 565 485 283 190 284 155       Cl 428 327 313 218 255 249 240     Br 362 285 243 201 217 249 216 190   I 295 213 --- 201 --- 278 208 175 149 Multiple Bonds C=C 602 C=N 615 C=O 799 CºC 835 CºN 887 CºO 1072 N=N 418 N=O 607 S=O (in SO2) 532 NºN 942 O2 494 S=O (in SO3) 469

4. Calculate the enthalpy of the reaction below, given the following: CHOH 1) + 202 () → 2CO2 ®+ 3H20 ay (g) + 3H2O m AHF CO2 = -393.5 kJ/mol AHf H2O = -285.8 kJ/mol * AHf C,H5OH =-277.7 kJ/mol %3D